Best Application Development Software for Emacs

The Windsurf Editor is a free AI-powered IDE and AI coding assistant that accelerates development by providing intelligent code generation and agents in over 70 programming languages and more than 40 IDEs, including VSCode, JetBrains, and Jupyter Notebooks. With Windsurf, developers can write code faster, eliminate repetitive tasks, and stay in the flow state—whether they're working with Python, JavaScript, C++, or any other language. Built on billions of lines of open-source code, Windsurf Editor understands and anticipates your coding needs, offering multiline suggestions, automated unit tests, and even natural language explanations for complex functions. It’s perfect for streamlining code writing, reducing boilerplate, and cutting down the time spent on documentation searches. Trusted by individual developers and Fortune 500 companies alike, Windsurf Editor is your go-to solution for boosting productivity and writing better code. Try Windsurf for free today!

Sourcetrail is an interactive source explorer that simplifies navigation in existing source code by indexing your code and gathering data about its structure. Sourcetrail then provides a simple interface consisting of three interactive views, each playing a key role in helping you obtain the information you need. Search: Use the search field to quickly find and select indexed symbols in your source code. The autocompletion box will instantly provide an overview of all matching results throughout your codebase. Graph: The graph displays the structure of your source code. It focuses on the currently selected symbol and directly shows all incoming and outgoing dependencies to other symbols. Code: The Code view displays all source locations of the currently selected symbol in a list of code snippets. Clicking on a different source location allows you to change the selection and dig deeper.

Scheme is a general-purpose computer programming language. It is a high-level language, supporting operations on structured data such as strings, lists, and vectors, as well as operations on more traditional data such as numbers and characters. While Scheme is often identified with symbolic applications, its rich set of data types and flexible control structures make it a truly versatile language. Scheme has been employed to write text editors, optimize compilers, operating systems, graphics packages, expert systems, numerical applications, financial analysis packages, virtual reality systems, and practically every other type of application imaginable. Scheme is a fairly simple language to learn since it is based on a handful of syntactic forms and semantic concepts and since the interactive nature of most implementations encourages experimentation. Scheme is a challenging language to understand fully.

Cody, Sourcegraph’s AI code assistant goes beyond individual dev productivity, helping enterprises achieve consistency and quality at scale with AI. Unlike traditional coding assistants, Cody understands the entire codebase, enabling deeper contextual awareness for smarter autocompletions, refactoring, and AI-driven code suggestions. It integrates with IDEs like VS Code, Visual Studio, Eclipse, and JetBrains, providing inline editing and chat without disrupting workflows. Cody also connects with tools like Notion, Linear, and Prometheus to enhance development context. Powered by advanced LLMs like Claude Sonnet 4 and GPT-4o, it optimizes speed and performance based on enterprise needs, and is always adding the latest AI models. Developers report significant efficiency gains, with some saving up to six hours per week and doubling their coding speed.

Wing Python IDE was designed from the ground up for Python, to bring you a more productive development experience. Type less and let Wing worry about the details. Get immediate feedback by writing your Python code interactively in the live runtime. Easily navigate code and documentation. Avoid common errors and find problems early with assistance from Wing's deep Python code analysis. Keep code clean with smart refactoring and code quality inspection. Debug any Python code. Inspect debug data and try out bug fixes interactively without restarting your app. Work locally or on a remote host, VM, or container. Wingware's 21 years of Python IDE experience bring you a more Pythonic development environment. Wing was designed from the ground up for Python, written in Python, and is extensible with Python. So you can be more productive.

Common Lisp is the modern, multi-paradigm, high-performance, compiled, ANSI-standardized, most prominent (along with Scheme) descendant of the long-running family of Lisp programming languages. Common Lisp is known for being extremely flexible, having excellent support for object oriented programming, and fast prototyping capabilities. It also sports an extremely powerful macro system that allows you to tailor the language to your application, and a flexible run-time environment that allows modification and debugging of running applications (excellent for server-side development and long-running critical software). It is a multi-paradigm programming language that allows you to choose the approach and paradigm according to your application domain.

JSON (JavaScript Object Notation) is a lightweight data-interchange format. It is easy for humans to read and write. It is easy for machines to parse and generate. It is based on a subset of the JavaScript Programming Language Standard ECMA-262 3rd Edition - December 1999. JSON is a text format that is completely language independent but uses conventions that are familiar to programmers of the C-family of languages, including C, C++, C#, Java, JavaScript, Perl, Python, and many others. These properties make JSON an ideal data-interchange language. JSON is built on two structures: 1. A collection of name/value pairs. In various languages, this is realized as an object, record, struct, dictionary, hash table, keyed list, or associative array. 2. An ordered list of values. In most languages, this is realized as an array, vector, list, or sequence. These are universal data structures. Virtually all modern programming languages support them in one form or another.

Extensible Markup Language (XML) is a simple, very flexible text format derived from SGML (ISO 8879). Originally designed to meet the challenges of large-scale electronic publishing, XML is also playing an increasingly important role in the exchange of a wide variety of data on the Web and elsewhere. This page describes the work being done at W3C within the XML Activity, and how it is structured. Work at W3C takes place in Working Groups. The Working Groups within the XML Activity are listed below, together with links to their individual web pages. You can find and download formal technical specifications here, because we publish them. This is not a place to find tutorials, products, courses, books or other XML-related information. There are some links below that may help you find such resources. You will find links to W3C Recommendations, Proposed Recommendations, Working Drafts, conformance test suites and other documents on the pages for each Working Group.

Dash gives your Mac instant offline access to 200+ API documentation sets. Dash is an API documentation browser and code snippet manager. Dash instantly searches offline documentation sets for 200+ APIs, 100+ cheat sheets, and more. You can even generate your own docsets or request docsets to be included. Dash comes with 200+ offline documentation sets. You can choose which documentation sets to download and Dash will take care of the rest, making sure they are kept up to date. You can also generate your own docsets, request docsets or download docsets from third-party sources. All documentation sets have been generated and are maintained with the utmost care. Dash integrates with package managers to generate documentation sets for anything you might need, as well as provide custom documentation sources of their own. Store snippets of code. Easily reuse snippets. Expand snippets in any app. Organize snippets with tags, syntax highlighting, and variable placeholders.

Magit is a complete text-based user interface to Git. It fills the glaring gap between the Git command-line interface and various GUIs, letting you perform trivial as well as elaborate version control tasks with just a couple of mnemonic key presses. Magit looks like a prettified version of what you get after running a few Git commands but in Magit every bit of visible information is also actionable to an extent that goes far beyond what any Git GUI provides and it takes care of automatically refreshing this output when it becomes outdated. In the background Magit just runs Git commands and if you wish you can see what exactly is being run, making it possible for you to learn the git command-line by using Magit. Using Magit for a while will make you a more effective version control user. Magit supports and streamlines the use of Git features that most users and developers of other Git clients apparently thought could not be reasonably mapped to a non-command-line interface.

After more than three decades of customer use and continuous enhancement, the MULTI Integrated Development Environment (IDE) is unmatched in the embedded software industry. Developers know they can rely on MULTI to help them produce high-quality code and get their devices to market faster. Whether pinpointing a hard-to-find bug, resolving a memory leak, or maximizing system performance, MULTI consistently works. Every feature of our revolutionary Debugger is designed to quickly solve problems that stump traditional tools. It often takes weeks or months to track down problems like inter-task corruptions, missed real-time requirements, and external hardware events. Green Hills' TimeMachine tool suite helps you solve the same problems in hours or even minutes. The TimeMachine tool suite automatically captures program execution data, combining the MULTI Debugger interface with innovative replay debugging capabilities.

Racket is a general-purpose, multi-paradigm programming language that serves as a modern dialect of Lisp and a descendant of Scheme. It is designed as a platform for programming language design and implementation, enabling developers to create new domain-specific and general-purpose languages. Racket's core language includes features such as macros, modules, lexical closures, tail calls, delimited continuations, parameters (fluid variables), software contracts, green threads, and OS threads. The language also comes with primitives, such as event spaces and custodians, which control resource management and enable the language to act like an operating system for loading and managing other programs. Further extensions to the language are created with the powerful macro system, which, together with the module system and custom parsers, can control all aspects of a language. Most language constructs in Racket are implemented as macros in the base language.

Hound is an extremely fast source code search engine. The core is based on this article (and code) from Russ Cox: Regular expression matching with a trigram index. Hound itself is a static React frontend that talks to a Go backend. The backend keeps an up-to-date index for each repository and answers searches through a minimal API. Currently Hound is only tested on MacOS and CentOS, but it should work on any *nix system. Hound on Windows is not supported but we've heard it compiles and runs just fine (although it helps to to exclude your data folder from Windows Search Indexer).

C is a programming language created in 1972 which remains very important and widely used today. C is a general-purpose, imperative, procedural language. The C language can be used to develop a wide variety of different software and applications including operating systems, software applications, code compilers, databases, and more.